The use of window frames and sashes in houses and buildings is well known. Typical construction of early window frames and sashes utilized wood, but attendant therewith were the problems of dry rot, warping and swelling. In an attempt to overcome such drawbacks inventors covered wood used in the construction of window frames with thin plastic extrusions. Such thin plastic extrusions served to delay warping and swelling, but actually tended to accelerate dry rot. A major advance was made with the introduction of aluminum window frames and sashes in that window frames and sashes made of aluminum are compact, and do not exhibit swelling, warping and dry rot, however, new problems presented. Said problems being sweating and associated high thermal conductivity. Attempts to overcome said sweating and high thermal conductivity problems included constructing window frames in which aluminum was utilized, wherein aluminum components were separated by thermally insulating wood. Another technique utilized plastic rails placed between aluminum elements. Such use of plastic led to fabricating window frames and/or sashes entirely therefrom. Plastic, however, is not as rigid as aluminum, hence, plastic extruded window frames tended to be bulky to provide sufficient strength. While the appearance of such bulky window frames and sashes is less than optimum, however, it should be appreciated that plastic has the benefit of not requiring periodic painting. It is noted at this point that present invention window sashes are produced by a resin transfer molding process, and comprise a more attractive, less bulky result, which incorporates thermal control and provides self contained wall trim, thereby enhancing ease of installation.
Inherent in the use of window frames and sashes is the interfacing of window sashes within window frames such that thermal insulating capabilities are achieved, while allowing window sashes to slide open and shut within said window frames.
A Search of Patents which relate to window frames and interfacing between window sashes and window frames has provided a Patent to Andars, U.S. Pat. No. 4,554,770. This Patent describes the use of small plastic buffers to reduce heat transfer in hollow aluminum frames. A primary purpose of the construction is to avoid gaps through which air might enter. A seal is provided between adjacent sashes by a separate removable intermediate interlocking rail.
Another Patent, to Gigeure, U.S. Pat. No. 4,674,246 describes a sliding window frame having two or more removable sash mounted therein, said window frame having head and sill made of thermally insulating plastic.
A French Patent to Armstadt, No. 1,420,069 describes a single glazed window in an aluminum frame without thermal breaks.
U.S. Pat. No. 3,324,597 to Rich describes a pair of window sash, one fixed and one slideable, with the two sash having leading edge interlocking weather strip flanges which may be interlocked on either side of the sash. The design focused on use in large size systems. Considerable separate finishing trim would apparently be required with the described system in practice.
A Patent to Nolan, U.S. Pat. No. 3,420,026 is disclosed as it describes an aluminum frame with thermal breaks. The focus is upon the use of thermal insulation to prevent or reduce condensation problems associated with metal frame windows or the like.
Another Patent, U.S. Pat. No. 3,111,726 to Grossman, describes window construction incorporating a horizontally slideable inner sash and an outer sash which is fixed. The frame involved is of multiple piece construction.
A Patent, U.S. Pat. No. 2,953,824 to Minick describes a system relating to window construction of the type including one or more fixed sash panels and one or more horizontally sliding sash panels all contained and supported within a frame in which all component sections (head, sill and side bar), are formed from extruded structural members.
U.S. Pat. No. 2,953,824 to Sharp describes a corner joint structure for application in sliding closure systems comprising a means for interconnecting a pair of frame members.
A Patent to Liebman et al, U.S. Pat. No. 2,869,187 describes a sliding type window construction comprising a metal frame.
A Patent to Vogelhut, Australian No. 222,834, describes a sliding door construction comprised of aluminum door panels, head, jamb and sill members.
U.S. Pat. No. 4,004,629 to Kelly describes a frameless sliding window assembly comprising a pair of jambs a header and a sill which are constructed from only two simple extruded shapes.
U.S. Pat. No. 3,861,444 to Portwood describes an extruded plastic window frame fabricated from extruded plastic components which are cut to length according to a given window size.
Finally, a Patent to Sherwood, U.S. Pat. No. 5,265,388 is disclosed as it describes a window frame assembly for mounting a window pane to a building. The outside and inside single piece construction frames each comprise radial projections which extend over outside and inside walls respectively. However, the window involved is not mounted in a slideable sash.
No known Patent describes various interface means affixed to a window sash, as taught by the present invention.
Continuing, with an eye to the present invention, a further Search of Patents which relate to sashes per se. was effected. Representative Patents which describe window sashes per se. include that to Pyzewski, U.S. Pat. No. 4,149,348. This Patent describes a sash which provides an adhesive secured spacer between glass sheets mounted therein, to form an insulating dead space between said glass sheets. A similar system is described in a Patent to Blaszkowski, U.S. Pat. No. 2,934,801.
Another Patent, U.S. Pat. No. 4,109,432 to Pilz, describes a window sash comprising a multipane insulating, extruded glass rim strip which has insulating space between panes. A method of producing the Pilz system involves providing an extruded strip with two grooves along an inner surface thereof, causing ninety (90) degree notches to be present at locations along said extruded strip which correspond to pane corners, heat softening said corner regions of said extruded strip and causing said extruded strip to be bent so as to conform to the shape of the panes. There is no circumscribing groove present in an outer surface of said extruded strip however. A method of realizing "framing channel structures" which utilizes ninety (90) degree notches and forming of a frame to a glass pane is described in U.S. Pat. No. 2,809,728 to Olson.
Patents which describe the presence of a groove in an outer circumference of a window sash are U.S. Pat. No. 2,708,774 to Seelen; U.S. Pat. No. 2,282,831 to Shutts; U.S. Pat. No. 2,173,664 to Shutts; U.S. Pat. No. 2,173,649 to Firner and U.S. Pat. No. 2,348,307 to Richardson. Said Patents, however, do not describe the mounting of various functionally effective interface means in said groove, as in the present invention. Another Patent, U.S. Pat. No. 5,131,194 to Anderson, however, describes the presence of a groove in an outer surface of a window sash, into which groove is caused to be mounted an elastomeric foam gasket. It is specifically noted that the foam gasket is non-rigid, emphasis added. The Anderson system is directed to providing a sound barrier, however, and not to providing easily mountable various functionally effective interface means to a window sash, in use. In particular, the groove means is not designed to allow easy affixing of various fuctionally effective interface means in use, nor is the foam gasket insert of a sufficient strength to support attachment of structural interface means.
A Patent to Johnson, U.S. Pat. No. 3,256,641 describes the presence of a guide rail secured to a window frame jamb by means of an element inserted into a groove in said window frame jamb. A portion of a Johnson sash is, by flanges, formed to slideably conform to the shape of said guide rail. Weather stripping can also be retained by said portion of a Johnson sash which is formed by flanges. However, a groove circumferentially present around the outer surface of a sash for allowing easy insertion thereinto of various interface means, as in the present invention, is not described.
A Patent to Sixsmith, U.S. Pat. No. 4,599,825 describes an interior storm window which secures a flexible plastic material with an inverted "U" shape therein, via end portions which extend into a pair of openings in an extruded rigid plastic material frame which surrounds a pair of glazing sheets. Again, a groove circumferentially present around the outer surface of a sash for allowing easy insertion thereinto of various functionally effective interface means is not described.
Other Patent of which the Inventor is aware, but which are not considered to be particularly relevant are: U.S. Pat. No, 4,510,715 to Giguere; U.S. Pat. No. 5,194,309 to Knudsen; U.S. Pat. No. 2,707,810 to Bolte; U.S. Pat. No. 4,118,266 to Kerr; U.S. Pat. No. 5,184,423 to McCarty; and U.S. Pat. No. 2,029,541 to Martinson.
There remains need for an improved window sash system which can be slideable, or otherwise, mounted in various window frames utilizing various interface means, said various interface means being easy to affix to circumscribing groove means present in an outer essentially planar surface of a window sash. Said improved window sash system should allow affixing different interface means at different location around a window sash circumference to simultaneously effect optimum mechanical and thermal interface results.